The present invention relates to a chelated additive for agro-zootechnical use in the broad sense, and in particular for alimentary use in the zootechnical sector, and the associated method for obtaining said additive. A chelate is a compound which is obtained from an organic molecule (in the case in question an amino acid or a peptide chain) and a metal ion by means of strong co-ordination bonds.
These compounds are widely used both in the agronomic field and in the zootechnical field since their usefulness is derived from the biological action of the metal involved, which acts as activator in a great number of enzymatic reactions and as regulator in various metabolic functions in all living organisms.
The presence of the bond with an amino acid material favours the absorption, availability and use of the metal since it is transported by the organic component to all areas of the organism.
Within the zootechnical sector in particular, these compounds are used in various breeding or rearing sectors to increase and strengthen the normal metabolic and functional activities of organs and apparatuses, with considerable positive effects on the capacities for productive growth of the animals.
The chelates currently present on the international market may be classified in various categories. The best known category is that which groups together the metal ions which form a complex with specific single amino acids. They are well definable compounds in terms of chemical composition and are easily assimilated and available for the organism.
A second category is composed of micronutrients which form a complex with single amino acids which, even though not well definable in this case, possess characteristics similar to those of the preceding group.
During production of these compounds, it was noted, moreover, that some soluble metal salts are difficult to chelate or leave undesirable residual products such as, for example, phosphoric acid or hydrochloric acid.
A third category contains metal ions which form a complex with several amino acids, preferably a maximum of three up to a molecular weight of 800 daltons.
The greater size of the molecule, however, results in a weaker bonding strength and greater difficulty of absorption.
A further category is composed of proteins which are obtained from the combination of a metal ion with a peptide chain. These compounds, the amino acid composition of which is not known, may interact with other substances contained in the food and therefore be of limited availability for the animal.
Finally, there are metals which form a complex with polysaccharide chains, in which the organic component has little effect on the real nutritional requirements of the animal and the metals are combined with organic acids, which are very soluble, but may easily dissociate in the intestines, with adverse effects in terms of lowering of the intestinal pH.
The object of the present invention is to obtain an additive for agro-zootechnical use and in particular for alimentary use in the zootechnical sector, in which a metal, which may also be classified among the micronutrients, is bonded to an amino acid via a strong chelating bond, this product being not only effective, but also stable and easily reproducible, and free from undesirable reaction by-products.
The objects are achieved by using a methionine in solution with an acid function (methionine hydroxy analogue) and reacting it with a carbonate of a bivalent metal, starting the reaction of the two components in particular with less methionine, relative to the carbonate.
Experiments carried out using the product thus obtained on dairy cattle have shown that the invention has positive and important effects on the animals.
Two groups of animals were prepared, one test group supplied with ordinary metal salts, and one experimental group supplied with the same quantity of chelated metal ions, but with the methionine hydroxy analogue according to the invention, in doses of about 10 g per head of cattle per day.
At the end of the test, the following results were observed in the treated group: a significant improvement in all the reproductive factors (fertility, succesful pregnancies, more rapid return to heat and improved ovary activity) and reduction in infections of the uterus and cases of mastitis following an improvement in the immune state of the animal, which allowed the latter to withstand effectively all the problems of an infective and metabolic nature which are typical of the postnatal period. Similar experiments were carried out on some meat cattle stock, distinguishing a test group from an analysis group and supplying the said groups with identical quantities of metal ions, one in salt form and the other in chelated form for about three months, in doses of about 10 g per head of cattle per day.
In this latter test, too, surprisingly a greater resistance to environmental stresses on the part of the animals, in the form of improved productive performances (growth and conversion factors, body growth), was noted. A reduction in podalic pathologies (laminitis, ulcers and interdigital dermatitis) was also detected.
The invention will emerge more clearly from the description of a working example illustrated below.